Images from a nearby galaxy may have explained how star factories can bizarrely slow down, astronomers reported on Wednesday.

Astrophysicists have long puzzled why the Universe has very few galaxies with a high mass, even though there are many galaxies that create stars at a phenomenal rate, sometimes a hundred times greater than our own Milky Way.

Massive leakage of methane from thawing shoreline in the Arctic would devastate the world's climate and economy, a trio of scientists warned on Wednesday.

Billions of tonnes of this potent greenhouse gas are locked in the shallow frozen shelf of the Arctic Ocean, which warms when summer sea ice retreats as a result of the greenhouse-gas effect, they said in a contribution to Nature.

Researchers in Switzerland say they have made microchips that imitate the way our brains process information, unlocking some of the mystery around how the world's most efficient computer functions.

Scientists at the University of Zurich and ETH Zurich, together with colleagues in Germany and the United States, created electronic systems comparable to a human brain both in size, speed and energy consumption, the university said in a statement late Monday.

Fine dangling filaments give mussels an extraordinary ability to cling to rocks and ship hulls and survive the ocean's battering, scientists said on Tuesday.

Mussels have long been feted for the glue with which they adhere to surfaces in the harsh marine environment -- a cement that chemists are trying to reproduce for industrial purposes.

The U.S. space agency said Tuesday it is launching a second investigation into a leaking helmet that forced an abrupt halt to an Italian astronaut's spacewalk last week.

The probe will examine maintenance, quality assurance, and any operations that could have had a role in the gushing water that mysteriously appeared in the helmet of Italian spacewalker Luca Parmitano.

Mexican paleontologists say they have uncovered 50 vertebrae believed to be a full dinosaur tail in the northern desert of Coahuila state.

The National Institute of Anthropology and History says the tail is about 15 feet (5 meters) long and resembles that of a hadrosaur or crested duckbill dinosaur.

More than half of Europe's main species of grassland butterflies are in sharp decline as a result of habitat loss, the European Environment Agency (EAA) warned on Tuesday.

"Butterfly populations have declined by almost 50 percent, indicating a dramatic loss of grassland biodiversity," it said.

Wild bottlenose dolphins design unique signature whistles to identify themselves, and they answer when a close cohort calls them by name, researchers said Monday.

A study of 200 bottlenose dolphins off the eastern coast of Scotland found that they are the only non-human mammals to use the names of those in their close circles to get each other's attention.

A towering plant that smells like rotting meat and is native to the Indonesian rainforest was in full bloom in the U.S. capital on Monday, drawing throngs of tourists.

The titan arum, among the world's largest plants, began blooming on Sunday at the United States Botanic Garden, and its petals are expected to stay open for just 24 to 48 hours.

A major Chinese state-owned coal producer has caused "drastic drops" in groundwater near one of its projects, the environmental group Greenpeace said in a report Tuesday.

Lakes have shrunk, wells have dried and sand dunes are spreading near a plant in Inner Mongolia run by coal conglomerate Shenhua Group, the organisation said.